Monday  |  Salon 9  |  04:10 PM–04:30 PM

#12743, Simplified Modeling and Modal Analysis of Timber Distribution Poles to Support Vibration-Based Condition Assessment

Timber distribution poles serve as the backbone of the electrical distribution network within the United States with over 130 million poles estimated to be currently in-service throughout the national grid. While timber is broadly utilized since it is typically the most economic option for this infrastructure, deterioration in timber poles caused by fungal decay and wood-damaging insects can result in significant section loss below the ground elevation that presents a structural deficiency that is not readily assessed without costly and time-consuming excavation of soil around the pole. Techniques for structural health monitoring and nondestructive evaluation, including vibration-based methods, have been investigated in numerous studies for their potential to provide a means to enhance safety assurance and asset management of timber distribution poles. In this paper, modeling of timber distribution poles with differing configurations is performed to provide insight into the effects of supported electrical infrastructure, anchorage, and embedment in the soil on the modal parameters of the pole. Experimental modal analyses conducted on timber distribution poles in both laboratory and in-service field conditions are used to support the assumptions incorporated into the models and provide evidence supporting the validity of the results. The influence of section loss developing below the ground line on the vibration response and modal parameters is also investigated through parametric analysis.

Timothy Kernicky   University of North Carolina at Charlotte
Matthew Whelan   University of North Carolina at Charlotte